Retrograde Peripheral Limb Perfusion For Formidable Femoral Arterial Access In Veno-Arterial Ecmo Treatment

Introduction: VA ECMO has emerged to a well-established therapeutic method in severe acute heart failure. In the case of peripheral ECMO placement, especially applying direct arterial cannulation, the limb perfusion is often compromised by an occlusive effect of the cannula positioned in the femoral artery. The classical proximal femoral arterial reperfusion branch provides sufficient blood flow via a small auxiliary cannula, but in patients with severe peripheral arterial vasculopathy or with significant tissue depth resulting from obesity, the placement of a peripheral arterial perfusion loop may pose a technical challenge. Methods: In case of emerging peripheral ischemic symptoms at femoral VA ECMO placement, ultrasound scanning of the lower limb vessels is performed. In an uncomplicated vascular situation, antegrade distal perfusion can be established. If a significant vasculopathy is present in the proximal vessels, or any further hindrances, including extreme obesity, physically not allowing a subtle perfusion cannula placement resulting from the discrepancy between the tissue depth and cannula length, retrograde peripheral perfusion could be established via the dorsal pedal artery utilising the Seldinger method. An ultrasonographic guidance is essential; hence there is sometimes no backflow present on the inserted cannula in a critically ischemic limb. Following sufficient de-airing manoeuvres, the retrograde femoral flow can be safely established; NIRS confirms the successful reperfusion in a short timeframe. If the dorsal pedal artery is not sufficient for cannulation purposes, the postmalleolar posterior tibial artery segment or the anterior tibial artery through the similarly named muscle can be utilised for cannulation purposes. Results: Two patients showed a pre-reperfusion calf saturation of 29% and 38%, which has increased to 61% and 64% after re-establishing the distal flow within minutes, respectively. We have experienced no complications emerging during the application of the above method. Conclusions: In case of peripheral vascular disease or the body habitus does not allow safe installation of an antegrade flow device, our retrograde perfusion option can save the affected limb on VA ECMO therapy.